Research continues in which the human electroretinogram and the visual evoked potential are recorded in response to alternating stimuli. In some cases alternation is produced by a visual stimulator; in others, it is produced by saccadic eye movement. Responses are recorded which result from stimulation of the peripheral retina as well as of the central regions. The methods may be used to obtain scotopic as well as photopic potentials, and current experiments are concerned with the Purkinje shift, the luminance-duration relation and the effects of the alpha rhythm on the VECP. Other stimulus variables are under examination including those of spatial frequency, movement, and color adaptation. An additivity model accounts for most current results. BIBLIOGRAPHIC REFERENCES: Armington, John C. The Correlation of Electrophysiological and Psychophysical Measures: The Electroretinogram, to appear in Documenta Ophthalmologica, 1977, 127-135, in press. Armington, John C. Electrophysiological Techniques for Studying the Visual Functions in Man, in Psychophysical Application of Human Electroretinography, William Benson, ed., Vision Committee, National Academy of Science, Washington, D. C., in press.